<meta charset="UTF-8">
<style type="text/css">
    span {
        display: inline-block;
        height: 150px;
        width: 25%;
    }

    div {
        height: 150px;
    }
</style>
<div>
    <div>头部</div>
    <div>导航</div>
    <div>
        <span>左</span>
        <span style="width: 49%">中</span>
        <span>右</span>
    </div>
    <div>头部</div>
    <div>导航</div>
</div>
